Due to recent advances in microelectronics technology, integrated circuits (also individually known as a “die”) now occupy less space while performing more functions. In order to provide electrical communication between the die and the external circuitry, the die can be secured to or contained within a package assembly that includes pins (also referred to herein as “contacts”) on one or more external surfaces of the package. The combination of the die and the package assembly is also referred to herein as an integrated circuit assembly.
The package assembly is physically secured to a substrate such as a printed circuit board, and provides an electrical connection between the die and interconnect pads on the surface of the substrate. To effectuate such a connection, a small solder ball can be secured to and/or forms a portion of each contact on the package assembly. These types of solder ball arrangements are often described as ball grid arrays (“BGA”). Today's conventional BGA devices can have spacings (also referred to herein as the “pitch”) of approximately 1.0 mm from center-to-center of adjacent solder balls. However, certain BGA devices can have decreased pitches (higher density of contacts) of less than 1.0 mm. For example, some BGA devices can have pitches of approximately 0.75 mm, 0.50 mm, or even smaller pitches.
To reduce the potential for selling defective products, the package assembly can be tested by a process that intentionally stresses the components to force early failures. In the semiconductor industry, this process is known as “burn-in”, and package assemblies are stressed using extremes of temperature and/or voltage with the objective of forcing failure of inherently weak components so that these defective devices can be sorted and discarded. For burn-in, one or more package assemblies to be tested are removeably mounted on or in a burn-in apparatus (also sometimes referred to herein as a socket board) that includes one or more sockets, each providing contact members that serve as electrical points of contact for each of the contacts of the package assembly while the package assembly is functionally tested, stressed and/or evaluated.
Unfortunately, the cost of manufacturing burn-in apparatuses that can accommodate higher density BGA devices, e.g., pitches of less than 1.0 millimeters, is relatively high compared to standard-sized burn-in apparatuses that accommodate BGA devices with pitches of 1.0 millimeters or greater. Additionally, reliably manufacturing burn-in apparatuses for small pitch BGA devices has become extremely challenging due to size limitations and constraints on the structures required by the burn-in apparatuses. For example, typical burn-in apparatuses include contact members having relatively large dimensions. As pitches of BGA devices decrease, inherent space limitations are imposed on the burn-in apparatuses. As a result, accommodating decreased-pitch BGA devices is increasingly difficult without significant modification of conventional burn-in apparatus structure and technology.